1. Field
Embodiments of the present invention relate to a control knob device, and more particularly, to a control knob device used in a vehicle or the like to control e.g., audio volume.
2. Description of the Related Art
A knob configured to turn on/off power, control volume, or change frequency is provided at a front panel of an audio-video (AV) system, which is installed in a vehicle, to protrude by a predetermined height.
In general, the height of the knob protruding from the front panel is 11 mm or more, and this is because the knob should protrude by the predetermined height or more so that a user may operate the knob manually. The protruding height of the knob may be 14 to 15 mm to provide a satisfactory feeling when a user operates the AV system.
However, the European automobile safety standard (ECE R-214), which defines vehicle internal components, defines that a component such as a switch and a pushing knob formed of a hard material should be reduced to a length of 9.5 mm or less, or should be chipped off for passengers' safety, when a vertical load having a certain force (37.8 daN) is applied thereto. The Indian automobile safety standard (IS15223:2002-4.1.5) also requires the above conditions. This is to prevent physical damage which may occur when a driver's head collides with the highly protruding knob.
The automobile-related industry has made continued efforts to satisfy the automobile safety standard having the most stringent conditions and also to satisfy the user's operation and esthetic preference. As part of these efforts, a design in which the front panel around the knob was recessed to be inclined was applied to improve feeling when the user grips the knob. However, the design had a problem in that the overall esthetic feeling of a vehicle interior was reduced, and satisfaction was not sufficient with the recessed portion. As another part of the efforts, it was considered to allow the knob break and contract at the time of collision. However, this caused inconvenience and repair cost due to the broken knob.
Korean Paten Publication No. 10-2009-0009466 discloses a shock absorbing structure of a knob for a vehicle audio system, which is capable of absorbing a shock having a certain pressure applied to the knob configured to operate the vehicle audio system and thus minimizing passenger injury due to contact with the passenger.